Atoms in reactions

In the case of the chlorine reactions, the involvement of H+ in the second step means that these reactions are efficient sources of chlorine atoms only at a pH less than about 4. Br can be converted to Br atoms in reactions analogous to those for chlorine, but in this case, generation of atomic bromine occurs up to a pH of about 11 (Zellner and Herrmann, 1995). 

For [Zn2], a rapid displacement of a Zn atom in reactions with alcohols and aUcenes was observed . This process is consistent with the weak bonding in the [Zn2]+ ion. 

One of the main products in each case was the expected 5,6-dihy-droxy-7-iodoindole,70,109,119, 1B1,166 which was invariably accompanied by some of the corresponding deiodinated product.1BB (The elimination of the halogen atom in reactions of this type has been referred to previously.109) Reduction of 7-iodoadrenochrome (12) with Na2S204 gives, besides 5,6-dihydroxy-7-iodo-V-methylindole (55) and 5,6-dihydroxy-iV-methylindole (28), the sodium bisulfite... 

The nature of the oxygen atom in reaction (15e) is not defined, although the rate constant given is for 0(3P). The reaction of 0(3P) [or O0D)] almost certainly does not give 02(1A9) as a product, and McGrath and Norrish104 appear to have been misquoted in this respect. 

The t-butyl isocyanide complexes of nickel(O) are used as starting materials for the synthesis of a number of complexes with unsaturated groups n bonded to the nickel atom in reactions similar to those given by dioxygen or diazo complexes (Sections 50.2.7.2 and 50.2.6.3). 

These are found from comparing the rates of a reaction in H20 and D20. They are usually a result of proton transfers between electronegative atoms accompanying the bond making and breaking steps between the heavier atoms in reactions such as the following ... 

The maximum quantum yield possible would be two, and using the absorbed light intensity, Ia, as the rate of formation of O atoms in reaction (24), the rate expression is... 

Reaction (11) will increase the apparent fraction of tin nonspecific route for calomel formation and consequently decrease the enrichment. The increase in enrichment and the decrease in [Pg.233]

Gallium trichloride is a solid (mp 78-79°) which reacts with air. It is soluble in both hydrocarbons and ether-type solvents. Both the solid compound and its solutions can be stored in a waterfree environment for relatively long periods. Gallium trichloride undergoes typical metathetical displacement of one, two, or all three chlorine atoms in reactions with one, two, or three molar equivalents of an alkyllithium compound, respectively 4... 

The driving force of these fluorinations is the weakness of the C — X (X = B. Si, Sn) bond, that facilitates ipso substitution of these functional groups by a fluorine atom in reactions with electrophilic fluorinating reagents and, in some cases, with elemental fluorine. 

The matrix on the left (a 3x4 matrix) is referred to as the conservation matrix because it gives the coefficients in the conservation equations for the reaction. The conservation equations for amounts n of C, H, and 0 atoms in reaction 7.1-1 are... 

W. H. Breckenridge, Reactions of Electronically Excited Atoms, in Reactions of Small Transient Species, edited by A. Fontijn, Chapter 4, pp. 157-230, Academic Press, London, 1983. 

Multiple cyclometallations with 2,8-diphenylnaphthyridine to prepare juxtaposed palladium atoms in reaction (o) could not be achieved. The tendency for palladium to form bridge bonds with halogen presumably prevents the palladium atom from inserting into another C-H bond of the aryl group. 

Here, M represents a third body solvent molecule, which is an acceptor of an excess energy released in each three-body recombination reaction. Hydrogen atoms in reactions (7.3) and (7.4) must be supplied from either photodissociation of solvent or H-atom abstraction reaction from solvent. 

Axworthy et a/. ° have reported the results of calculations on the combustion generation of F atoms in reactions of potential use in an HF continuous-wave laser. Various combinations of oxidizers (Fj, N2F4, NF3, CIF5, CIF3) and fuels were considered. 

Hydrogen atoms as intermediates occur in many reactions. In view of evidence obtained in numerous investigations, the participation of adsorbed hydrogen atoms in reactions discussed in Sections IV, V.A., VI.B, VI.C, and VII has, therefore, been assumed without explicit proof. The following typical hydrogen transfer reactions are quoted. 

J 2 kg. of iodine, no crystals being allowed to fall below the platinum foil or glass wool. The iodine is covered with part of 2000 cc. (50 moles) of methanol (Note 7), the rest of which is added to 200 g. each of red and yellow phosphorus (12.8 gram atoms) in reaction flask D. 

Once an oxygen atom is generated in reaction 1 (above), reactions 2 and 3 proceed rapidly. The characteristic time for reaction of the O atom in reaction 2 is... 

Figure I. Velocity vector diagrams for Reactions 1 and 2 illustrating the striking improvement in kinematics for detection of product T atoms in Reaction 2 as compared with detection of product KBr molecules in...

The cis or trans relation of the chlorine atoms in reactions (c) and (d) is reported to be retained in the corresponding cyclobutane adducts by Schenck et These authors favour a mechanism involving a biradical complex of sensitiser and anhydride as the actual entity attacking the olefin. 

Table 6, Effects of Substituents Located at the C° Atoms in Reactions of Solvolysis and Dehydration...

Chemical analysis data indicate that, on the average, 3.0-3.8Cl atoms per Hf atom are replaced in reactions of diols with HfCl, and 1.5-1.7 Cl atoms, in reactions with CpjHfCl. Given this, we took into account the possible formation of oxobridges in calculating the compositions of the condensation-type Hf-containing polymers from chemical analysis data (Table 10.1). 

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